#include <iostream>

class Test //final // final : 不允许被继承 最终类
{
public:
    Test() = default; // 按默认方式构建函数
    Test(int a) {}
    virtual void show()
    {
        std::cout << "Test" << std::endl;
    }
};

class Derived : public Test
{
public:
    void Show()
    {
        std::cout << "Derived" << std::endl;
    }
};

int main()
{
    Test *t = new Derived;
    t->show();
    return 0;
}
